As you may know by now, the Los Angeles County Sheriff’s Department has dusted off — yet again — its investigation into the actress’ drowning in waters off Santa Catalina Island (about 20 miles off the California coast) on Nov. 29, 1981. (She was just 43 years old.)

The fresh reopening of the case occurs some seven years after Dennis Davern, the captain of the yacht Splendour, co-authored a book — and told a TV network — that he had lied to authorities about what actually had happened aboard the vessel on the night Wood disappeared. He urged that the incident be re-examined.

Now, investigators say two new witnesses have come forward to buttress Davern’s account, specifically that Wood and husband, actor Robert Wagner, had a nasty ‘alcohol-fueled’ fight just prior to her disappearance.

That, as you’ll see, does not appear to be new information. What may be new is what investigators told the CBS-TV program, 48 Hours — that bruises on Wood’s body suggest she had been struck. She looked like a victim of assault, said one detective.

Some backround: On a sunny California morning, Wood’s body — clad in a down-filled red parka — was fished out of waters near Catalina harbor. A vacant dinghy was found in an isolated cove. The death was ruled at the time as an accident.

Wood, actor Christopher Walken (her costar in Brainstorm, the movie she was making) and her husband Wagner (maritally, the second time around for both) were the only passengers aboard the Splendour besides Davern. They were taking a Thanksgiving holiday cruise.

While the case of Wood’s drowning is being re-opened, Wagner, who turns 88 next week, is not a suspect. He is, however, more of a person of interest now, say investigators.

Whatever his classification, the best account of what happened on that late November night (that we know of) is contained in a harrowing chapter — titled, Everything Went Away From Me – in Wagner’s own 2008 memoir, Pieces Of My Heart: A Life, co-authored by Scott Eyman.

The actor doesn’t conceal the fact that alcohol, a nasty marital spat and friction with Walken all played a role that night. According to his book, on the afternoon and early evening of Nov. 27, Wood, Wagner and Walken went shopping on Catalina Island, then stopping off at a favorite watering hole where the three W’s ordered margaritas and beer chasers.

Natalie was a bad swimmer, and feared the water although she felt comfortable aboard the Splendour. After returning to the yacht, we had some more drinks over dinner, recalled Wagner. By this time we had had slightly too much to drink, and things were getting combative.

Following an argument with her husband, Wood demanded to leave the yacht and spend the night at a motel on Catalina Island. But she returned the next morning to the Splendour and, wrote Wagner, everything was fine.

The three W’s napped aboard the yacht that afternoon. Wagner remembered that when he woke up he found a note from Natalie saying that she and Walken had taken the dinghy and gone (to a restaurant on the island). I wasn’t angry, but I was agitated.

Wagner joined Walken and his wife at the restaurant where we had quite a bit of wine with dinner. More drinks followed when they returned to the yacht.

Then, Chris began talking about his ‘total pursuit of a career,’ which he admitted was more important to him than his personal life. He clearly thought that Natalie should live like that too… Wagner wrote that at this point in the conversation, he had had it. ‘Why the fuck don’t you stay out of her career?’ I said. ‘She’s got enough people telling her what to do without you.’

A heated argument ensued, and Wagner recalls slamming a wine bottle on a table, shattering it into pieces. Natalie was already belowdecks at that point….The last time I saw my wife she was fixing her hair at a little vanity in the bathroom while I was arguing with Chris Walken. I saw her shut the door. She was going to bed.

Wagner wrote that he never viewed Wood’s body; I wanted to remember her alive. An autopsy showed that the actress had an alcohol level of .14, slightly above the .10 level of intoxication for California.

After painfully trying for decades to reconstruct that night’s events — did Wood slip and fall unconscious into the water while trying to retie a loose dinghy? — Wagner finally concluded, the bottom line is that nobody knows exactly what happened.